Automatic bank of elevator cars



Nov. 6, 1951 D. SANTINI ETAL AUTOMATIC BANK OF ELEVATOR CARS 9 Sheets-Sheet 1 Filed June 9, 1950 Fig.l.

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n I o D INVENTORS Dcnilo Somini,PhHIip C.Keiper andgolter H.Esselmcn.

ATTORNEY WITNESSES: 4

Nov. 6, 195] D. SANTINI ETAL 2,573,932

AUTOMATIC BANK OF ELEVATOR CARS Filed June 9, 1950 9 Sheets-Sheet 2 u up aws a [4 Fug. 3. Donilo Somini,Phil|ip C.Keiper I ondgalier C. Esselmon. {in} 2 47 am ATTORNEY Filed June 9,

D. SANTHNE ET AL AUTOMATIC BANK OF ELEVATOR CARS 1950 9 Sheets-Sheet 6 QUF @UHS mma SUF Emma

WITNESSES:

LE- U INVENTORS Danilo SrJmini,Phillip Keipev and welfer H.Essemon.

' @JZMM ATTORNEY Nov. 6, 1951 D. SANTINI ETAL 3 AUTOMATIC BANK OF ELEVATOR CARS Filed June 9, 1950 9 Sheets-Sheet 8 kL8+ *U L :4

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BZDL B2 53 v alusz Mose L L L uo+ LIO- F i g],

WITNESSES: INVENTORS 547/? Duniio SonfingPhiHip QKeiper und volterHEsselmon.

ATTORNEY D. SANTINI EI'AL 2,573,932 AUTOMATIC BANK OF ELEVATOR CARS 9 Sheets-Sheet 9 Nov. 6, 1951 Filed June 9, 1950 wmmu man 33 mam o ng m2 Ac -35 mom uo mmon won a? $3 mom A? 33 m9 3&3.

HNVENTORS Denim summiymnm QKeiper magma? Hfiwelmora.

ATTORNEY WITNESSES: 5% $44 AUTOMATIC BANK OF ELEVATOR CARS Danilo Santini, Tenafly,

Phillip C. Keiper,

Shrewsbury, and Walter H. Esselman, Cranford, N. J., assignors to Westinghouse Electric Corporation, East Pittsburgh, Pa., 9. corporation of Pennsylvania Application June 9, 1950, Serial No. 167,202

21 Claims. 1

This invention relates to multicar elevator systems and it has particular relation to automatic multicar systems wherein elevator cars are started in response to operation of a service control located at each of the floors served by the elevator cars or by service controls located in the elevator cars.

In conventional multicar automatic elevator systems, it has been the practice to locate each of the elevator cars in a bank in a separate hatchway. Each of the hatchways is provided with a hatchway door for each of the floors served by the elevator car. The elevator cars operate between terminal floors and serve a plurality of intermediate floors. Each of the intermediate floors is conventionally provided with an upservice control and a down-service control which are common to all of the elevator cars. The upper terminal floor is provided with a downservice control and the lower terminal floor is provided with an up-service control which again are common to all of the cars in the bank. In addition, each of the elevator cars is provided with a control for each of the floors served by the elevator car.

When no demand for service exists in the system, the elevator cars are at rest and all of the doors are closed. In response to operation of a service control, one of the elevator cars is conditioned to answer the demand for service from the operated service control.

In the conventional multicar automatic elevator system of the type herein discused, a service control at an intermediate floor may be operated while an elevator car is at rest at such floor with its adjacent hatchway door closed. Under such circumstances, the operated service control merely opens the hatchway door and permits the entrance into the elevator car of a prospective passenger. Inasmuch as no direction preference is established for the elevator car and inasmuch as no indication is given of thenext direction of travel of the elevator car, prospective passengers waiting for transportation have no assurance that the elevator car will travel in the direction desired by each of the prospec tive passengers. As a matter of fact, certain of the prospective passengers may desire transportation to a lower floor or to various lower floors whereas the remainder of the passengers may desire transportation to one or more higher floors of the building or structure.

In accordance with the invention, operation of a service control at an intermediate floor while an elevator is parked at the floor with its hatchway doors closed operates not only to open the hatchway doors at the floor of the operated control, but additionally operates a signal immediately to indicate the next direction of travel of the elevator car. At this time, a direction preference is given to the elevator car which conditions the elevator car for travel in the direction corresponding to the operated service control.

In some cases, a prospective passenger who has operated a service control at an intermediate floor while an elevator car is parked thereat may fail to enter the elevator car after the hatchway doors have opened, the direction signal has been operated and the direction preference has been established for the elevator car. Under such circumstances, the hatchway doors are reclosed, the direction preference is cancelled and the signal is restored to its unoperated condition after the lapse of a predetermined time measured from the operation of the service control.

In multicar automatic elevator systems wherein the driving motors for the elevator cars are energized from energy-transforming devices, such as motor-generator sets, the energy-transforming devices may be deenergized when no demand for service exists for the elevator system. When the next demand for service is received, the motor-generator set for other energy-transforming device for one of the elevator cars is started or energized. To prevent frequent starting operations of the motor-generator sets or other devices, a time delay may be provided which must elapse after the elevator car has answered all calls for service before the motor-generator set associated therewith may be shut down. In a multicar elevator system, one of the elevator cars may be selected as the next car to answer the next demand for service from the system.

In accordance with the invention, if the selected car is at a predetermined floor, such as the lower-terminal floor, with its motor-generator set shut down and a second elevator car reaches the lower-terminal floor before the next service demand is received, the selection of the next car to answer the next service demand is transferred to the elevator car having its motorgenerator set still in operation. This eliminates the necessity for starting the shut-down motorgenerator set and also eliminates the necessity for shutting down the motor-generator set of the elevator car which has just reached the lowerterminal landing.

It is, therefore, an object of the invention to provide an elevator system wherein operation of provide a multicar elevator system having energytransforming devices which are deenergized when the elevator cars are parked with meansfor transferring the selection of the next car to answer a demand for service from a car having its energy-transforming device deenergized to an elevator car having its energy-transforming device energized.

Other objects of the invention will be apparent from the following discussion taken in conjunction with the accompanying drawings, in which:

Figurel is a view in side elevation with parts broken away of an elevator system which may embody the invention;

Fig. 2 isa view in front elevation with parts broken away of a floor selector suitable for the system of Fig. 1;

Fig. 3 is a schematic view showing control circuits in straight lineform suitable for the system of Fig. 1

Fig. 3A is,a schematic view or key showing relays and switches employed in the circuits of Fig. 3. For groups of relays or switches having showing still further control circuits suitable for the elevator system of Fig. 1; I

Fig. 6A is a schematic view or key figure showin relays and switches employed in the circuits of Fig. 6. For groups of relays and switches having similar functions only representative members of the group are illustrated in some cases in Fig. 6A. If Figs. 6 and 6A are placed in horizontal alignment, it will be found that corresponding coils and contacts of the two figures are substantially in horizontal alignment.

. Fig. 7 is a schematic viewin straight line form showing signal circuits suitable for the system of Fig. 1; and

Fig. 7A is a schematic view or key figure showing relay contacts employed in the circuits of Fig. 7 If Figs. '7 and 7A are placed in horizontal alignment, it will be found that the corresponding contacts of the two figures are substantially in horizontal alignment.

e Features of applicants invention may be employed in single, car or multicar systems which with reference to the system shown in the Carney similar functions only representative members of the group are illustrated in some cases in Fig. 3A. If Figs. 3 and 3A are placed in horizontal alignment, it will be found that corresponding coils and contacts of the relays and switches shown in the two figures are substantially in horizontal alignment;

Fig. 4 is a schematic view in straight line form showing further control circuits suitable for the elevator system of Fig. 1; v

Fig. 4A is a schematic view or key showing relays and switches employed in the switches of Fig. 4. For groups of relays or switches having similar functions only representative members of the group are illustrated in some cases in Fig. 4A. If Figs. 4 and 4A are placed in horizontal alignment, it will be found that corresponding coils and contacts of the two figures are sub,- stantially in horizontal alignment.

Fig. 5 is a schematic view in straight line form showing additional circuits suitable for the elevator system of Fig, 1;

Fig. 5A is a schematic view or key figure of relays and switches employed in the circuits of Fig. 5. For groups of relays or switches having similar functions only representative members of the group are illustrated in some cases in Fig. 5A. If Figs. 5 and 5A are placed in'horizontal alignment, corresponding coils and contacts. of the two figures will be found to be substantially inh'orizontal alignment.

Fig. 6 is a schematic viewm'straight line form et al. Patent 2,172,187, which issued September 5, 1939. Insofar as possible, the conventions employed in the Carney et al. patent will be adhered to in the present discussion. Components of the Carney et al. system which are herein illustrated will be identified by the same reference characters employed in the Carney et al. patent.

Apparatus in Fig. 1

Figure 1 is identical with Fig. 1 of the Carney et al. patent and the similar components of .the two figures operate in identical manner except as hereinafter set forth. For this reason, a detailed discussion of the components is believed to be unnecessary at the present time. However. for convenience, the following components appearing in Fig. 1 are listed as follows:

The asterisk indicates that a contact segment and a brush have been added to the floor selector employed in the Carney et al. patent. These additions will be discussed below. These changes in the floor selector represent the only differences between Fig. 10f the present patent application and Fig. 1 of the Carney et al. patent.

Apparatus in Fig. 2

p Fig '2v shows the selector r's' which is employed in the system of Fig. 1. The apparatus of Fig. 2

morass:

is identical with the apparatus shown in Fig. 2 of the Carney et al. patent except for the addition of a brush I which is secured to the brush arm 46. By inspection of Fig. 2, it will be observed that the brush I00 engages the contact segment He only when the elevator car is at the lower terminal floor, in this case the first floor.

Apparatus in Fig. 3

The apparatus in Fig. 3 includes the following components which also appear in Fig. 3 of the Carney et al. patent:

l8, brake coil '20, rotor 2 I, 22, 23, stator windings U, up-direction switch or relay D, down-direction switch or relay Ll, L2, L3, conductors of source of electrical energy ms to US, up-stopping relays ms to SDS, down-stopping relays UP, up-preference relay "DP, down-preference relay TE, hesitating relay M, control-conditioning relay.

The asterisks indicate that contacts have been added to the relays to which the asterisks are applied. Except for this addition of contacts, the components set forth in the foregoing list are identical with the corresponding components of the Carney et al. patent and operate in the same manner.

In some elevator systems, it is the practice to employ motor-generator sets or other energytransforming devices for energizing elevator drivlng motors. Thus in a variable-voltage drive a motor-generator set having a direct-current generator is employed for energizing a direct-current elevator driving motor. An aspect of the invention is applicable to such a motor generator set. However, such Carney et al. patent shows an alternating-current motor and the aspect of the invention can be described with reference to a motor-generator set employed for energizing the alternating current motor. Therefore, in order to further simplify the presentation of the invention, it will be assumed that the alternatingcurrent driving motors of the Carney et al. patent are energized from motor-generator sets. Thus in Fig. 3 a switch 50 is disclosed which is identical with the switch 50 of the Carney et al. patent. In the Carney et al. patent, the switch 50 is energized directly from the conductors Ll, L2. L3 of a three-phase alternating-current circuit. In the present case, the switch 50 is energized from an alternating-current generator l0l which is rotated at a uniform rate by means of a motor W2. The motor I 02 and the generator IOI constitute a motor-generator set which may be employed for providing a voltage for the motor l5 which differs in magnitude or in frequency or in both magnitude and frequency from that provided by the conductors Ll, L2 and L3. The motor W2 is energized from the conductors Ll, L2 and L3 through a suitable motor starter which is here represented by contacts MGI, MG2, M63 of a starter switch.

As shown in Fig. 3, the starter switch MG is energized from the buses L4+ and L4 through make contacts DPS or UPS of the down preference relay or the up preference relay.

Except for the insertion of the break contacts ttUZ of an up assignment relay between the break contacts 5USl and DPS and except for the insertion of the break contacts 42Dl of a down assignmeat relay between break contacts UP3 and IDSI, the sequence circuit 8. is associated with the buses L4+ and L4- and the up preference relay UP and the down-preference relay DP in exactly the same manner by which the sequence circuit SI of the Carney et. al. patent is associated with the preference relays and the buses. If the break contacts 4202 and DI of Fig. 3 are closed, the preference relays UP and DP are energized and deenergized in exactly the same manner by which the preference relays UP and DP of the Carney et al. patent are energized and deenergized.

When the elevator car A is parked at a floor with the hatchway doors for the floor closed. the up preference relay UP or the down preference relay DP may be energized promptly upon energization of an up-service control or a downservice control for the aforesaid floor. These service controls may be the call push buttons IUF to 4UF and ZDF to 5DF which are located at the floors and which are shown in Fig. 5. Under these circumstances, the up-preference relay UP is energized through the make contacts HUI of the up-assignment relay and the break contacts DPS of the down-preference relay. In an analogous manner, the down-preference relay DP would be energized through the make contacts D2 of the down-assignment relay and the break contacts UPS of the up-preference relay. When one of the preference relays is energized in this manner, the sequence circuit Si is rendered ineffective by opening one of the sets of break contacts "U2 or "DI.

Apparatus in Fig. 4

The following components appear in Fig. 4:

IE to SE, car buttons IC to SC, holding coils ICN to SCN, cancellation coils Y, auxiliary car preference relay 1, inductor relay Q, door interlock relay 55, car-door-safety contact members l-54 to 5-54 hatchway-door-safety contact members ITF to 5TF, field windings of door motors lTA to STA, armatures of door motors ZF, field winding of car-gate motor ZA, armature of car-gate motor NF, field winding of control motor NA, armature of control motor W, door control relay DC, door closing relay DO. door opening relay Fig. 4 is identical with Fig. 4 of the aforesaid Carney et al. patent except that some additional contacts are provided for the door interlock relay Q, as indicated by the asterisk. Since the various relays of Fig. 4 operate in the same manner set forth in the Carney et al. patent, a detailed discussion thereof is considered unnecessary.

Apparatus in Fig. 5

Fig. 5 corresponds to the upper portion of Fig. 5 in the aforesaid Carney et al. patent. The relays V, BV, H and BH of the Carney et al. patent also appear in the present Fig. 5 and operate in substantially the same manner. However, the brushes 34, 31, B34 and B31 are connected to the bus L8- in a somewhat diiferent manner which will be discussed below (in Fig. 5 of the Carney ctsaztl. patent, the brush B3! is labeled erroneously B The following apparatus is common to the presntsFigTfi and" to-Fig. ofthe Carney et ah patent 'andoperates in substantially the same manner.

Referring now to the changes incorporated in the present Fig. 5, it will be noted that the brush 34 (which cooperates with the contact segments ldto 4d) is-connected to the bus L8 through the following circuit 34,DP5. nu, K2 or in, M10, L8

If the cancellation coil IURN is energized (the up call button IUF is operated), if the elevator car is not conditioned for down travel (the break contacts DPS are closed) and if the elevator car is not in running condition (the break contacts MID are closed) the up-assignment relay 42U may be energized. However, if the doors are open,

the break contacts Q3 of the door interlock relay are closed to shunt the relay 42U and prevent energization thereof. Furthermore, if the elevator car has just arrived at the first floor, the make contacts TE2 of thehesitating relay are closed to establish a shunt around the relay 42U. Consequently, energization of the relay 42U would have to await timing out of the hesitating relay TE. In a similar manner, the brush 34 cooperates with any of the contact segments Id to id, de pending on the position of the elevator car.

In a somewhat similar manner, the brush 31 is connected to the bus L8 through the break contacts UP5, the down assignment relay 42D, contacts K2 or HI and break contacts MI 0. For this reason, if the cancellation coil for any of the floors is energized through the brush 31', if the break contacts UP5 are closed (the elevator car is not conditioned for up travel) and if the car is not in running condition (the break contacts Mltl are closed), the down-assignment relay may be energized. The down-assignment relay energization is controlled further by break contacts Q4 and make contacts TE3 of the door interlock and hesitating relays in a manner which will be, understood from the discussion of the shunting of the relay "U by the contacts of the corre-E sponding relays. V a

The purpose of the relays "U and 42D is to establish a direction preference when the elevator'car A is parked at a floor with its doors closed and when one of the call buttons for the floor-is operated by a prospective passenger. *These relays flU and 42D have a substantial delay in dropout for reasons which will be understood from a discussion of the operation of the system to be presented below.

As explained in the aforesaid Carney et a1.

' patent, the switch 25 is employed for selecting the next car to answer a call for .service when more-than one of the elevator cars are parked at the-same fioor. In the Carney et al. patent, the switch 25 is manually operated and it may be manually operated in the present system. However, automatic operation of the switch 25 also is-provided by apparatus which now will be dis-- cussed. a v

'As shown in Fig. 5, the switch 25 is secured aemlk ns been! lqlwhichbag l ga ds. n v a secured--to .xmagetic armatures I04 and 165.-

These armatures have forces ap'plied theretwby. means of solenoids IBM and a.- Thus the solenoid HIM-may be energized through thefollowing circuit- L54 a, BMGQ, Blot, Blk, L8- In an analogous manner, the solenoid lfita may be energized through the circuit fm+ new, Mac, we, 1m, L8-

I If the switch 25 is in engagement with. the con-.

.would remain in engagement with the contact 25a. Similar comments apply if the switch 25 is in engagement with the contact 25b and the solenoid lflda is thereafter energized. If the elevator car A is parked at a floor with its motor-generator set shut down and ifthe elevator car A is selected as the next car to respond to a call for service and if the elevator car B thereafter arrives at the same floor, the selection of the next car to answer a call for service would be transferred from the car A to the car B. This eliminates the necessity for starting the motor-generator set of the elevator carA to answer a call for service. Since the call for service may be received before the motor--, generator set of the carB shuts down, it is clear that a substantial saving in the operation of the motor generator set results. Similar comments apply if the elevator car B is parked at afioor with its motor-generator set shut down and if it is selected as the car to answer the next call for service.

' The transfer of the selection of the next car to answer a call for service may take place at any desired floor or floors. For the purpose of the present discussion, it is assumed that such transfer is desired only at the lower terminal fioor. Consequently, the contact segments 1k and. Elk are located to engage the brushes we and Bind only when the associated elevator cars are at the .first floor.

Apparatus in Fig 6 Apparatus in Fig. 7

The present invention contemplates the provision of a signal for indicating at each floor the direction of travel of an elevator car which is about to leave the floor. Although various types of signals may be employed, it will be assumed that up and down floor lanterns will be provided at each of the intermediate floors for each of the elevator cars. In addition, for each of the elevator cars a down floor lantern is locatedat the upper terminal floor and anup floor lantem-is located at the lower terminal floor. The down floor lanterns for the second to fifth floors are,

d ai fi q by the si enqapbara te mum;

IDL, respectively. In an apalogous manner, the up floor lanterns for the first to fourth floors are identified by the reference characters IUL to UL, respectively. The down floor lanterns 2DL to BL may be energized respectively through make contacts of the down stopping relays 2DS to SDS. In an analogous manner, the up lanterns for IUL to JUL may be energized respectively through make contacts of the up stopping relays I US to US, respectively. The energizing circuit for the up lanterns is completed through make contacts UP'I of the up-preference relay and break contacts Mil of the control conditioning relay. The energizing circuit for the down floor lanterns is completed through make contacts DPI of the down preference relay and the break contacts Mil of the conditioning relay. The down floor lantern for the upper terminal floor additionally may be energized through the circuit 1.8+, SDL, 5US2, UPI, Mil, L9-

In an analogous manner, the up floor lantern for the lower terminal floor may be energized through the circuit L9+, IUL, IDSZ, DPT, Mil, L9

The buses or conductors L4+ to Ll and L4- to Ll0 may be energized from the conductors Ll, L2, L3 through rectifiers if the circuit components require direct-current energization. However, as in the case of the Carney et al. patent. the circuit components are assumed to be energized with alternating current supplied through the buses from the conductors Ll, L2, L3.

OPERATION Inasmuch as the aforesaid Carney et al. patent discusses the operation of many components of the system, it is believed that a brief discussion particularly directed to the additions to the Carney et al. system herein described will suffice.

It will be assumed that the elevator car A is located at the third floor and that no calls for service are registered in the elevator system. Furthermore, it will be assumed that the elevator doors are closed and that the motor-generator sets are shut down. The elevator car B may beassumed to be located at the fifth floor. The car-selecting relay H is assumed to be energized.

Inasmuch as the elevator car doors are closed, the relay Q (Fig. 4) is energized. Furthermore, since the elevator car A is located at the third floor with no direction preference established, the break contacts DPI and UPi (Fig. 3) both are closed and the stopping relays 3US and 3DS both are energized.

The door control relay W (Fig. 4) is energized through its associated break contacts M9 and W. The car preference relay X (Fig. 6) is energized through the circuit 138+, H2, UB6, 3UR6, 3a, H, X, B31, Bid, H3, L8-

Since the make contacts XI (Fig. 4) are closed, the auxiliary car preference relay Y is energized.

With the system in the condition just described, it is assumed that the down-call button SDF is operated by the prospective passenger at the third floor. Such operation of the call button completes the following circuit (Fig.

1.8+, ms, 372, 38, ps4, v, K2: and Elfin parallel,

Mill, L8-

As a result of its energization, the auxiliary door relay V opens its break contacts Vi (Fig. i) to 7 deenergize the door control relay W. The relay W, in turn, closes its break contacts W2 (Fig. 4) to complete an energizing circuit for the door opening relay DO. The door opening relay operates in the manner described in the Carney et al. patent to open the car gate and hatchway doors for the elevator car A.

At the same time, the operation of the call button 3DF' established the following circuit 1.8+, 3DF, BDRN, 3g, 31, UPS, 42D, K2 and HI in parallel, Mill, Ll-

When the call button was initially operated all the doors were closed and the door interlock relay Q was energized. Inasmuch as the break contacts Q4 were open, the down service relay "D was energized.

The energization of the down service relay 42D results in opening of the break contacts "DI (Fig. 3) to render the sequence circuits ineffective. In addition, the make contacts 42D! close to establish the following circuit 1.4+, 42m, UP3, DP,

The energization of the down preference relay DP conditions the elevator system for down operation in the manner set forth in the aforesaid Carney et al. patent.

As a result of the opening of the doors for the elevator car A, the door interlock relay Q is deenergized. This relay recloses its break contacts Q3, but such reclosure has no immediate effect on the system. In addition, the break contacts Q4 close to shunt the down assignment relay 42D. However, this relay has a time delay in dropout and remains picked up for a time sufllcient to permit entry of passengers into the elevator car.

When the prospective passenger, releases the call button 3DF, he deenergizes the auxiliary door relay V. The auxiliary door relay V recloses its break contacts VI (Fig. 4) to reenergize the door control relay W.

The energization of the down preference relay DP not only operates in the manner set forth in the Carney et al. patent, but it also completes an energizing circuit through the contacts DPS (Fig. 3) for the starter switch MG. This switch closes its make contacts MGI, MGZ and MG3 to start the motor-generator set for the car A. In addition, the starter switch closes its make contacts MG! (Fig. 5) but this has no immediate effect on the operation of the system.

Referring to Fig. 7, it will be noted that the energization of the down-preference relay DP resulted in closure of the make contacts DP'I. Since the make contacts 3DS3 are closed, the following circuit is established L9+, 3DL, 3DS3, DP'I, Mll, L9-

Consequently, the operation of the call button for the third floor results not only in establishment of a down preference for the elevator car A, but it also illuminates the down floor lantern 3DL to indicate to all prospective passengers on the third floor that the elevator car A is conditioned for down travel.

It will be assumed next that a passenger enters the elevator car A and that the doors reclose in the manner set forth in the aforesaid Carney et al. patent. It will be recalled that energization of the door closing relay DC and the resultant closure of the doors results in reenergization of the door interlock relay Q. The relay Q not only operates its contacts Qi and 1 Ii Q2 in the manner set forth in the aforesaid Carney et al. patent, but it opens its break contacts Q8 and Q4 (Fig. 5) Such opening has no immediate eifect on the operation of the system.

If the passenger desires to proceed to the first fioor he operates the car button IE. The operation of the car button IE deenergizesithe auxiliary car preference relay Y (Fig. 4) and finally results in energization of the down direction switch D and the control conditioning relay M to condition the car for down travel in the manner set forth in the aforesaid Carney et al. patent. In addition, the relay M opens its break contacts Mil (Fig. 7) to deenergize the down lantern lDL.

The elevatoncar approaches and stops at the first floor in exactly the same manner discussed in the aforesaid Carney et al. patent. It will be recalled that asthe car reaches the first floor, the down stopping relay IDS (Fig. 3) is energized and this relay consequently closes its break contacts IDS: (Fig. 7). As the elevator car comes to rest, the break contacts DPI (Fig. 3) also close to energize the up stopping relay IUS and this results in closure of the make contacts IUS2 (Fig. 7). However, as long as the elevator car is at rest, the make contacts UP! and DP! of the preference relays are open and the lantern for the first floor cannot be illuminated.

Let it be assumed that after the elevator car A has reached the first floor and after the elevator car doors have opened and reclosed, a prospective passenger at the first floor operates the up call push button IUB (Fig. 5). This establishes the following energizing circuits Id, 34, DPI, 2U, K2 or HI, MIO, LI-

It is assumed that the elevator car has been at the first fioor for a time sufilcient for the hesitation relay TE to time out. Consequently, the make contacts TE2 are open. Also, the elevator car doors are all closed and the break contacts Q3 of the door interlock relay are open. Therefore, no shunt is established across the up assignment relay 2U and this relay is energized. It will be recalled that the relay 2U has a time delay in dropout and remains picked up even though the button IUF is released and the energization of the cancelling coil IURN prevents a registration of the fioor call.

The energized up-assignment relay 2U closes its make contacts HUI (Fig. 3) to energize the up preference relay UP. In addition, the break contacts "U2 open to render the sequence circuit 80 ineffective. The relay UP operates in the maner set forth in the Carney et al. patent. In'addition, it closes its make contacts UP to energize the starter switch MG. Consequently, if the motor-generator set for the car A has become shut down, the energization of the starter switch MG restarts the motor-generator set. If

the starter switch has not yet dropped out, the closure of the make contactsUPt reenergizes the starter switch to prevent it from dropping out.

In addition, the make contacts UPI (Fig. '7) close to complete the following circuit Consequently, the operation of the up-call push button IUF has resulted not only in the establishment of a direction preference for the elea 12 vator car but it has illuminated the up fioor lantern IUL to indicate to all prospective passengers at the first floor that the elevator car" is conditioned for up travel. The illumination of the fioor lantern IUL continues until a passen g'er entering the elevator car presses ac'anbiitton. The resulting energization of the control conditioning relay-M opens the break contacts (Fig. 7) to deenergize the floor lantern IUL. However, should a passenger fail to enter the ele-- vator car, the up assignment relay 42U (Fig. 5) would drop out to deenergize the up preference relay UP (Fig. 3). The deenergization of the up preference relay UP would terminate the direction preference of the elevator car and would extinguish the floor lantern iUL (Fig. 7).

-Itwill be recalled that as long as no demand for service exists on the system, the motor-generator sets are shut down. However, after an elevator car has supplied the necessary service for the last call for service, the motor-:generator set for such elevator car remains energized for a predetermined time. If one of the'elevator cars has its motor-generator set in operation and if the other elevator car or cars have a motor generator set or sets shut down, it is desirable that the elevator car with its motor generator set in operation be selected as the next elevator car to answer a demand for service. This is particularly true of one of the floors such as the lower terminal floor at which one or more of the elevator cars normally may be parked. The operation of the system under such circumstances now will be considered.

' It will be assumed that the elevator car A is parked at the first floor with its motor-generator set shut down. The car selecting switch 25 (Fig. 5) has been positioned to engage the contact 25a and to energize the car selecting relay H. Consequently, if both of the elevator cars A and B are at the first floor, the elevator car A is selected as the next car to answer a call for service.

Inasmuch as the elevator car A isat the first fioor, the brush its is in engagement with the contact segment Us 01 the floor selector. However, since the starter switch MG is deenergized, the make contacts MG! are open and the sole noid iota is deenergized.

It will be assumed next that the elevator car B is approaching the first floor and that no further calls for service exist on the system. Inasmuch as the elevator car B is in operation, its starter switch is energized and the make contacts BMGl are closed. As the elevator car B reaches 'the first floor, the brush BIN engages the contact Blk to complete the following energizing circuit L8+, a, BMGl, BIOO, Blk, LB-

As a result of energization of the solenoid 505a, the switch 25 is actuated into engagement with the contact 251). Such operation of the switch deenergizes the car selecting relay H and energizes the car selecting relay BH. Consequently, the car B now is selected as the next elevator car to answer a call for service. Since the motorgenerator set of the car B continues in operation for a predetermined time after the elevator car B reaches the first floor, any call for service received between the time of arrival of the elevator car B at the first floor and within the dropout time of the starter relay BMG does not require a restarting of any motor-generator set.

Although the invention has been described with reference to certain specific embodiments 13 thereof, numerous modifications falling within the spirit and scope of the invention are possible.

We claim as our invention:

1. In an elevator system for a structure having terminal and intermediate landings, driving means for moving the elevator relative to the structure for serving the landings, each of said intermediate landings having an up service control and a down service control operable by a person desiring respectively up or down elevator service, and control means responsive to an operation of one of said controls while the elevator car is positioned at the landing of the operated control with no direction preference established therefor for conditioning the elevator car for movement in the direction of travel corresponding to the operated control.

2. A system as claimed in claim 1 wherein said control means establishes said conditioning of the elevator car only for a predetermined time measured from the operation of the operated control.

3. A system as claimed in claim 1 in combination with an up signal and a down signal located at each of the intermediate landings, each oi said signals being operable only when the car is at or adjacent the corresponding floor and is free to provide service in the direction of the associated signal, and means responsive to an operated one of said controls while the elevator car is positioned at the landing of the operated control with no established direction preference for operating the signal of such landing which corresponds in direction to the operated control.

4. A system as claimed in claim 3 in combination with means for cancelling said conditioning and the operation of one of the signals after the lapse of a predetermined substantial time, measured from the operation of the operated control responsible for such conditioning and operation.

5. In an elevator system for a structure having terminal and intermediate landings, driving means for moving the elevator relative to the structure for serving the landings, each of said hitermediate landings having an up service control and a down service control operable by a person desiring respectively up or down elevator service, an up signal and a down signal located at each of the intermediate landings, each of said signals being operable only when the car is at or adjacent the corresponding floor and is free to provide service in the direction of the associated signal, and means responsive to an operated one of said controls while the elevator car is positioned at the landing of the operated control with no established direction preference for operating the signal of such landing which corresponds in direction to the operated control.

6. A system as claimed in claim 5 in combination with means for cancelling an operated one of said signals after the lapse of a predetermined time measured from the operation of the control responsible for such signal while the car is at the floor oi the operated control.

7. A system as claimed in claim 5 in combination with means responsive to the approach of the elevator car to the floor of the operated control while the car is free to answer such control for operating the signal corresponding to the operated control.

8. A system as claimed in claim 5 in comloination with means effective while the elevator car and control means are in condition for normal running of the elevator car for maintaining the signals extinguished.

9. In an elevator system for a structure having terminal landings and a plurality oi intermediate landings, a plurality of elevator cars, independent driving means for moving each of the elevator cars relative to the structure for serving the landings, a common up service control and a common down service control at each of the intermediate landings, control means responsive to operation of one of said controls while any one of the elevator cars with no direction preference established therefor is stopped at the landing of the operated control for conditioning such stopped elevator car for movement in the direction of the operated control.

10. A system as claimed in claim Qwherein said control means establishes said conditioning only for a predetermined time measured from the operation of the operated control.

11. A system as claimed in claim 9 wherein the control'means is effective if a plurality of the elevator cars with no direction preference established are stopped at the landing of the operated control for selecting only one of the elevator cars for said conditioning.

12. A system as claimed in claim 9 in combination with an up signal and down signal at each of the intermediate landings for each of the elevator cars, and signal operating means responsive to operation of a selected one of said controls while one of the elevator cars is positioned with no established direction preference at the landing of the selected one of the controls for operating the signal corresponding to the selected one of the controls for the lastnamed car.

13. A system as claimed in claim 12 in combination with means for cancelling said conditioning and said operation of one of the signals after the lapse of a predetermined substantial time measured from the operation of the operated control responsible for such conditioning and operation.

14. In an elevator system for a structure having terminal landing and a plurality of intermediate landings, a plurality of elevator cars, independent driving means for moving each of the elevator cars relative to the structure for serving the landings, a common up service control and a common down service control at each of the intermediate landings, an up signal and a down signal at each of the intermediate landings for each of the elevator cars, and signal operating means responsive to operation of a selected one of said controls while one of the elevator cars is positioned with no established direction preference at the landing of the selected one of the controls for operatin the signal corresponding to the selected one of the controls for the last-named car.

15. A system a claimed in claim 14 in combination with means for cancelling said operation of one of said signals after the lapse of a predetermined substantial time measured from the operation of the operated control responsible for such operation.

16. A system as claimed in claim 14 in combination with a motor-generator set for each of the elevator cars, starter means for starting each of the motor-generator sets and means responsive to operation of said selected one of the controls for starting the motor generator set of the elevator car responding to the operated signal.

aeraese 17. A system as claimed in claim 14 wherein the signal operating means i effective if 'a plurality. of .the elevator cars are stopped with no direction preference established. at the landing of the operated control for operating the=signalof only a selected one of the elevator cars.

18. A system .as claimed in claim 17 in combination with a motor-generator set for each of the elevator cars, starter means for starting each of .the motor-generator sets and means re-' sponsive to operation of said selected one of the controls for starting the motor generator. set of the=.elevator car responding to the operated signal:

19: In an elevator system for a structure having terminal landings and 'a plurality'of inter mediate landings, a plurality of elevator cars". independent driving mean for moving each or the elevator cars relative to the structure for serving the landings, a common up service con trol' and a common down service control at each of the intermediate landings, a motor-generator set 'foneach of the elevator cars, and control means responsive to the operation of a selected one of said controls while two of the "elevator cars are positioned at a landing with the motorgenerator set for only one of the. two generator sets in operation, with the car having the motorgenerator set out of operation selected as the next car to respond to a call for service prior to the arrival of the remaining one of the two cars at said landing, and with no calls'for service registered prior to the operation of saldselected one of said controls, for assigning the call from the selected one of said controls to the car having the operating motor-generator set.

20. In an elevator system for a structure have ing terminal and intermediate landings, first and second elevator cars, first and second independent driving means for driving respectively the: first and second elevator cars relative to the structure for servin the landings, a common up service'control and a common down service con,-

trol at; each of the intermediate landings, a first motor generator set and a second motor-generator set for energizing respectively the first and second driving means, andcontrol means responsive to the operation'of a selected one of said controls while the first elevator car is stopped at a landing with the first motor-generator set shut down for starting the first motor.-

a landing with both of the motor-generator sets I shut down when a call is registered by the call means'fo'r starting only-one of the motor-generator set and only one of the cars in response to such call." I

c. KEIPER. V

H. ESSELMAN.

No references cited. 

